The undefeated son of Candy Ride set the pace, turned away a challenge from graded stakes winners Gormley and Iliad, and pulled away in the stretch to win by 6 ¾ lengths at Santa Anita Park. But Mastery was pulled up by Mike Smith after the wire, and the Hall of Fame jockey jumped off the colt in the turn.
Cheyenne owner Everett Dobson said after the race that Mastery sustained a condylar fracture in his left front leg and will undergo surgery "in a few days."
"It will require a few screws to be inserted and he's going to have to take some significant time off—several months off," Dobson said. "Obviously it's incredibly disappointing. It's difficult to find horses of this talent and have them run in your colors."
Mastery was taken off the track, back to trainer Bob Baffert's barn, in a horse ambulance as a precaution. Smith said he felt something wrong about "10 jumps" after the finish line.
"Something went off on the left hind. I don't know why," Smith said. "It wasn't something that happened that made me think, 'Oh [something wrong] happened.' He just all the sudden went off it and wouldn't put any weight on the left hind.
"I got off real quick and nothing is dislocated and everything seemed fine, and after he moved for a little bit, he started walking fine on it. I'm hoping maybe he just tweaked it or rolled it and that it's nothing serious, because he's an incredible horse."
Baffert was making his way down to the winner's circle after the victory when a fan alerted him something had gone wrong.
"Assistant trainer Jimmy [Barnes] said he didn't see anything obvious when he went on the trailer," Baffert said. "We've been so high on this horse and you see what he did today, which was incredible ... and I'm walking down and I hear one of the fans say, 'I hope your horse is all right.'"
The trainer later said that the colt will be re-evaluated after surgery.
"We won't know until after the surgery whether or not this will be career ending," Baffert said.
In the San Felipe, Mastery hit the front soon after the start, with Gormley stalking, and Iliad sitting just off the top two. Mastery set fractions of :23.50, :46.76, and 1:10.48 through six furlongs, when Gormley mounted his serious challenge entering the far turn. As Gormley began to drop back, Iliad loomed as a challenger, but Mastery effortlessly pulled away in the stretch. His margin over Iliad was two lengths with a furlong to run, and he extended it with each stride to the wire to finish off the 1 1/16 miles in 1:42.28.
"This is a really talented horse," Smith said. "The power is endless with this guy. He's some kinda strong. He was hitting gears every time I asked him to. ... Everything seemed to come easy to him. That was a pretty impressive race. I'm just hoping everything is OK."
Mastery gained 50 Kentucky Derby qualifying points with his win in the San Felipe, giving him 60 total. He is 4-for-4 in his career, including a win in the Los Alamitos Cash Call Futurity in December.
Iliad, in his two-turn debut, finished 1 ¾ lengths clear of Term of Art, who rallied from last in the seven-horse field to pass Gormley late for third. Ann Arbor Eddie, Bluegrass Envy, and Vending Machine completed the order of finish.
"Between the three-eighths [pole] and the quarter pole, I thought I could catch him," said Iliad's jockey, Flavien Prat. "This was the first time around two turns and he ran really well. He should improve off of this race."